First of all, there are no more rich clubs like Bayern Munich in the Bundesliga. Secondly, neither team probably wants to compete with Bayern Munich for the title. The Dortmund team is quite strong. Had Dortmund not sold their best players every season they could have built a squad capable of competing for the title with Bayern Munich. But they don't. And this is why we see only Bayern Munich's dominance in the Bundesliga every season. Next season we will see the dominance of Munich.
Borrusia Dortmund keep trying each year to match up energy with Bayern but it seems impossible. The previous season, they were very close but got unlucky at the end. In the coming decades, the Bavarians will win over their opponents. Bayern Munich will continue to dominate the Bundesliga because they have what other teams are missing: players and a meticulously designed resources. The Bavarians have dominated the league on every occasion. Even though they started the season unfavorably they seem to be finding their way; it was a sophisticated performance from both the players and the coach.